Compile-time rational arithmetic

From Cppreference

[edit] ratio

Defined in header `<ratio>`

template< intmax_t Num, intmax_t Denom = 1 > class ratio;		(C++11 feature)

The class template ratio provides compile-time rational arithmetic support.

Several convenience SI typedefs are already provided:

Defined in header `<ratio>`

typedef std::ratio<1, 1000000000000000000000000> yocto; //see below typedef std::ratio<1, 1000000000000000000000> zepto; //see below typedef std::ratio<1, 1000000000000000000> atto; typedef std::ratio<1, 1000000000000000> femto; typedef std::ratio<1, 1000000000000> pico; typedef std::ratio<1, 1000000000> nano; typedef std::ratio<1, 1000000> micro; typedef std::ratio<1, 1000> milli; typedef std::ratio<1, 100> centi; typedef std::ratio<1, 10> deci; typedef std::ratio<10, 1> deca; typedef std::ratio<100, 1> hecto; typedef std::ratio<1000, 1> kilo; typedef std::ratio<1000000, 1> mega; typedef std::ratio<1000000000, 1> giga; typedef std::ratio<1000000000000, 1> tera; typedef std::ratio<1000000000000000, 1> peta; typedef std::ratio<1000000000000000000, 1> exa; typedef std::ratio<1000000000000000000000, 1> zetta; //see below typedef std::ratio<1000000000000000000000000, 1> yotta; //see below		(C++11 feature)

The typedefs yocto, zepto, zetta, yotta are provided only if intmax_t is sufficient to represent the values used to instantiate the templates.

[edit] ratio arithmetic

Several class templates, that perform arithmetic operations on ratio objects at compile-time are provided.

Defined in header <ratio>

ratio_add (C++11)

adds two ratio objects at compile-time
(class template)

ratio_subtract (C++11)

subtracts two ratio objects at compile-time
(class template)

ratio_multiply (C++11)

multiplies two ratio objects at compile-time
(class template)

ratio_divide (C++11)

divides two ratio objects at compile-time
(class template)

[edit] ratio comparison

Several class templates, that perform comparison operations on ratio objects at compile-time are provided.

Defined in header <ratio>

ratio_equal (C++11)

compares two ratio objects for equality at compile-time
(class template)

ratio_not_equal (C++11)

compares two ratio objects for inequality at compile-time
(class template)

ratio_less (C++11)

compares two ratio objects for less than at compile-time
(class template)

ratio_less_equal (C++11)

compares two ratio objects for less than or equal to at compile-time
(class template)

ratio_greater (C++11)

compares two ratio objects for greater than at compile-time
(class template)

ratio_greater_equal (C++11)

compares two ratio objects for greater than or equal to at compile-time
(class template)